i seen on another forum you were fixing a racing jam 2 rtc error,you never replyed how you got on,i have the same problem and was wondering ig the mame file worked you nflashed on the M48T58 chip.
ooo bummer im not sure of my version but its not jap,the other side of the game still works,but i dont know how to get the data off and back on toa new chip,i have a willems eeprom programmer,havent used it yet so its all new.
if you can help me ill send you the code from the good working chip,might be the same.